1. Field of the Invention
The present invention relates to an image processing apparatus, and more particularly, to an image processing apparatus intended to achieve an improvement in the efficiency of image retrieval.
2. Description of the Related Art
In recent years, digital electronic still cameras designed to record photographed images on a digital recording medium, such as a semiconductor memory card or a small hard disk (an optical disk), in the form of digital signals have been developed and are available on the market. Such digital recording media have a structure which allows the data recorded thereon to be read out with a personal computer.
Since image data can generally be recognized only when a human being looks at them, when image data are reproduced, a list of a plurality of reduced images may generally be displayed so that the user can check the contents of image files, using the reduced images themselves as the retrieval images.
However, in retrieval display of reduced images, since an entire image is simply reduced to, for example, one eighth in both its longitudinal and lateral dimensions, the reduced image may be too small to be recognized easily, making the use of that reduced image as a retrieval image impossible. In the case of, for example, an image photographed from a document, character data may be reduced to a size which makes decoding of the data almost impossible. Thus, in the case of a document shown in FIG. 1 in which desirable retrieval data to be offered to the user are, for example, titles in the document (such as "SUMMARY OF THE INVENTION" in the case shown in FIG. 1), if an entire image is reduced, most of the characters become too small to be decoded, making achievement of the original purpose, retrieval image display, impossible.